Borna Coric gave Croatia a flying start in their Davis Cup World Group semi-final against the United States, defeating Steve Johnson 6-4, 7-6(4), 6-3 in the opening rubber in Zadar on Friday.
The 21-year-old Coric had lost his only previous encounter with the U.S. number three at Roland Garros but on Zadar's clay courts drew first blood for the hosts against Johnson, who was leading his country in the absence of John Isner and Jack Sock.
Coric's emphatic win just underlined why the Croats, who had won all their four previous ties with the Davis Cup's most successful nation, were overwhelming favourites to repeat the dose and reach the final of the last Davis Cup to be played in its traditional historic format before next year's revamp.
Both Coric, the world number 18, and Marin Cilic, number six, are ranked significantly higher than their first-day singles opponents with U.S debutant, 20-year-old Frances Tiafoe, facing the former U.S. Open champion in the second rubber.
Coric was impressive from the start, taking an early break for 2-1, aided by Johnson missing plenty of first serves, and controlling the 35-minute opening stanza.
The youngster brought the crowd to their feet with one extraordinary 'tweener' lob that left Johnson flat-footed as he earned another quick break in the second set but the American fought back strongly to take it to a tiebreak.
Coric again stepped up his game, reeling off the final four points of the breaker, featuring a glorious forehand winner and a fine volley, to seal it 7-4.
He then forged home his advantage over the world number 30 in the third set to wrap up victory in two hours and 24 minutes and take Croatia's seventh straight win in their favourite Zadar venue.